A maintenance system for maintaining a scalable printhead array comprises: a pair of tracks disposed in parallel and on opposite sides of a printhead array; a shaft extending between the tracks and configured to engage with each track to move along the tracks; a plurality of maintenance modules mounted in series along the shaft between the tracks and configured to move along the tracks with the shaft to perform maintenance operations on a plurality of printheads of the printhead array, the tracks being configured to guide the shaft and the plurality of maintenance modules along a path from a resting position to an operating position the printhead array and from which at least one of the plurality of maintenance modules performs a maintenance operation on at least one printhead of the printhead array; and an actuator configured to move the shaft along the tracks.